This is an open-label, multiple-dose, pharmacokinetic, safety and antiviral activity study of three dosing regimens of oral lobucavir in HIV-infected subjects who have plasma viral load of at least 10,000 HIV-RNA copies/ml within 14 days of randomization. Lobucavir is a guanine nucleoside analogue with a broad spectrum of antiviral activity in tissue culture models. Activity against DNA virus infections includes: Herpes simplex viruses and varicella zoster virus. The mechanism of action for lobucavir is inhibition of DNA polymerase by LBV-TP. Lobucavir-triphosphate acts by inhibiting viral DNA polymerase and by terminating nascent DNA chains. In animal models of HSV and CMV infection, lobucavir demonstrated significant protection. It is thought that lobucavir may have antiviral activity against HIV and this study will address that issue through testing of HIV-RNA levels. The endpoints of the study are pharmacokinetics, HIV viral load, CMV urine culture, CD4 counts, and safety.